Dissolved neodymium concentrations and isotopic composition from the full water column in the South Pacific Ocean during SONNE cruise SO289 (GEOTRACES section GP21)

This dataset contains dissolved neodymium (Nd) concentrations and radiogenic Nd isotope compositions from full water-column seawater profiles collected in the South Pacific Ocean during the GEOTRACES section GP21 (Chile to New Caledonia) aboard R/V SONNE (cruise SO289) between 23 February and 4 April 2022.Between 10 and 40 L of seawater were collected using 10 L Niskin bottles mounted on a stainless-steel CTD rosette. Beginning at Station 18, an additional 40 L of surface seawater was collected using a trace-metal-clean tow-fish to enable Nd isotope measurements at expected low concentrations.Samples for Nd isotope analysis were pre-concentrated onboard by coprecipitation with Fe hydroxide and later purified in the home laboratory before analysis by MC-ICP-MS (Thermo Neptune Plus). Nd concentrations were determined from 1 L acidified seawater aliquots spiked with a ¹⁵⁰Nd spike, processed via Fe-hydroxide coprecipitation and AG 50W-X8 cation exchange purification, and measured by isotope-dilution MC-ICP-MS with external reproducibility better than 0.2%.